Load take-up apparatus for lifting devices

ABSTRACT

Load take-up apparatus for lifting devices, more particularly spreaders for container lifting devices with retaining means which bear upon and grip the load, more particularly rotating bolts which are disposed at the corners of the spreader and are lockable in fittings of the container wherein the retaining means, more particularly the rotating bolts are supported on the load take-up device in resilient, yielding manner.

ilnited States Patent Bechtloif 11] f 357mm Mar. 18, 1975 LOAD TAKE-UP APPARATUS FOR LlUFTlNG DEVICES [75] Inventor: Gert Bechtloif, Brucker Str. 12, 294

Wilhamshaven, Germany [73] Assignee: Friedrick Koclrs GmbH, Bremen,

Germany 22 Filed: June 7, 1973 21 Appl. No.: 367,940

[30] Foreign Application Priority Data June 8, 1972 Germany 2227823 [52] US. Cl 294/81 SF, 294/67 DA [51] Int. Cl. B66c 1/42 [58] Field of Search 294/81 SF, 81 R, 67 D,

294/67 DA, 67 B, 67 R, 82 R, 83; 308/72; 24/221 R, 221 K, 221 L [56] References Cited UNITED STATES PATENTS Abegg 294/82 R X 2,570,320 10/1951 Christensen 294/82 R X 2,654,643 10/1953 Reese 308/72 2,766,079 10/1956 Browne... 308/72 3,677,599 7/1972 Shannon 294/67 DA Primary Examiner Richard A. Schacher Assistant Examiner-James L. Rowland Attorney, Agent, or FirmSughrue, Rothwell, Mion, Zinn & Macpeak [57] ABSTRACT 11 Claims, 1 Drawing Figure LOA-D TAKE-UP APPARATUS FOR LIFTING DEVICES The invention relates to a load take-up apparatus for lifting devices, more particularly spreaders for container lifting devices with retainingmeans which bear upon and grip the load, more particularly rotating bolts which are disposed at the corners of the spreader and are lockable in fittings of the container.

The invention relates in first place to problems which arise when containers are loaded by means of container bridges and the like. .The lifting device of such container bridges is provided with a spreader suspended from the hoisting ropes and intended for taking up the container. If a container is to be taken up from a storage area, forexample the quayside or the storage deck of a ship the spreader is placed from above on the container. The retaining means, namely rotating bolts, which are disposed at the corners of the spreader, enter into fittings on the corners of the container and are locked therein by rotation.

In view of the turn-round speeds which are required at the present time it is evident that spreaders are placed upon the containers at substantial lowering speeds. Substantial mass forces therefore become effective which result in severe impact loadings being applied to the container as well as to the spreader and its fittings. To some extent this leads to severe damage of individual components which cannot be designed to withstand such impact loadings. The mass forces and the risk of damage is particularly severe when a container is taken up within a compartment in the ship. The crane driver has no visibility in this zone so that he is unable to observe the operation of placing the spreader on the container. The prior art does not disclose devices by means of which the free space under the spreader may be inspected.

It is the object of the invention to develop and improve such load take-up devices, more particularly spreaders for containers in the sense that impact loadings which are unavoidable during loading operations have none or only slight consequences for the loads or the load take-up device.

To solve this problem, the load take-up device according to the invention is characterized in that the re taining means for taking up the loads, more particularly the rotating bolts, are resiliently supported on the load take-up device, more particularly on the spreader. The retaining device or rotating bolt respectively is preferably supported on a spring with strong natural damping, for example on a resilient buffer block-of plastics material with a large work-absorption capacity.

The impact loadings which occur as the result of the spreader bottoming at a high lowering speed and because ofthe substantial mass forces caused thereby, are absorbed by the damped spring in such a way that the kinetic energy is substantially absorbed by the resilient element. The retaining means or the rotating bolt respectively are or is thus prevented from springing back suddenly.

Further details will be explained by reference to the embodiment of the invention as illustrated in the accom panying drawing. The drawing represents a vertical section through retaining means, namely a rotating bolt according to the invention on a spreader.

The load take-up device, more particularly a spreader may be constructed in suitable manner. Of

this spreader the drawing shows only the outer lower corner which is provided with retaining means, namely a rotating bolt 11, fortaking up the load, in this case a container. The lower zone of the rotating bolt 11 is constructed in such a way that it is able to enter into a fitting disposed on the top of the container and may be locked in the said fitting by being rotated.

According to the invention the rotating bolt 11, which bears on the container when the spreader I0 is lowered thereon, is resiliently supported. In the illustrated preferred embodiment the rotating bolt 11 is rotatably guided in a bearing member 12 which in turn is part ofa carrier 13. The upper wall 14 ofthe carrier 13, which is constructed as a hollow member, bears upon a spring which in the present case is constructed in the form of a resilient buffer block 15. The buffer block 15 is disposed in a housing 16 surrounding the said block, the carrier 13 being guided and supported therein so as to be vertically slidable. To this end, the carrier 13 is located in the housing 16 so that the buffer block 15 is under prestress when the rotating bolt 11 is unstressed in such a way that only increased loadings on the rotating bolt 11 result in a damped resilient motion of the carrier 13 accompanied by compression of the buffer block 15. The housing is rigidly coupled to the spreader 10.

The carrier 13 is supported in the housing 16 so as to merely permit axial motion but no rotating motions. To this end, a lower zone 17 ofthe carrier 13 is constructed to have a polygonal circumferential surface. This bears positively on a surface of a zone 18 on the inside of the casing 16, said surface being also of corresponding polygonal construction.

The carrier 13 is provided not only for accommodating'the rotating bolt but also for accommodating any actuating and monitoring elements such as electric and hydraulic drives, switching apparatus and safety circuits. In the illustrated embodiment this includes a tracer pin 19 the function of which is to monitor the operation of locking of the locking bolt in the fitting of the container. The tracer pin 19 is adjoined by a flexible conduit 20 which transmits the signals ofthe tracer pin 19 to a limit switch or the like. The deformability of the conduit 20 permits axial motions of the rotating bolt 11 or of the carrier 13 respectively without damage to the conduits and connections.

An actuating arm 21 by means of which the rotating motions for locking the rotating bolt 11 are transmitted thereto is attached to the same end by means of a separate bearing 22 to the upper end of the rotating bolt 11. The said bearing 22, by means of which primary pivoting motions of the actuating arm 21 are to be transmitted to the rotating bolt 11 in one plane as rotating motions, is constructed with spherical bearing surfaces 23 which are adapted to compensate for axial motions of the rotating pin 11.

The buffer for absorbing the increased impact load ings may also be constructed as a mechanical spring with a shock damper, for example a hydraulic shock damper.

I claim:

1. In a shock absorbing load take-up apparatus for containers having a supporting frame and rotatable bolts disposed thereon and adapted to be inserted into corresponding fittings in the container, the improved rotatable bolt mounting comprising:

a. an outer housing attached to said supporting frame,

b. an inner housing attached to said rotatable bolt and coaxially mounted within said outer housing so as to slide relatively thereto in a direction parallel to the longitudinal axis of said outer housing,

c. resilient buffer means interposed between one end of said inner housing and one end of said outer housing, and

d. means to prevent relative rotation between said inner and outer housings.

2. A device as claimed in 1 wherein the inner housing supports all actuating and monitoring elements such as electric and hydraulic drives, switching apparatus and safety trip circuits.

3. A device as claimed in claim 1 wherein a downwardly extending tracer pin, adjoined by a flexible conduit, is disposed in the inner housing. I

4. Apparatus as claimed in claim 1 wherein said resilient buffer means is under prestress.

5. The improved load take-up device of claim 1 wherein said resilient buffer means comprises a cellular plastic material, such as polyurethane, having a high work absorption capacity.

6. The improved load take-up device of claim 1 wherein said resilient buffer means comprises an by draulic damper.

7. The improved load take-up device of claim 1 wherein said means to prevent relative rotation comprises:

a. an opening in said outer housing having a polygo nal cross section, and

b. a correspondingly polygonal extension attached to said inner housing and extending through said opening in said outer housing.

8. The improved load take-up device of claim 7 wherein an actuating arm for causing rotary movement of said rotatable bolt is attached to said extension by means of a spherical bearing.

9. The improved load. take-up device of claim 1 wherein said bolt is rotatably attached to said inner housing.

10. The improved load take-up device of claim 1 wherein an actuating arm for causing rotating movement of said rotatable bolt is attached to said bolt by means of a spherical bearing.

11. The improved load take-up device of claim 1 wherein said inner and outer housings are generally cylindrical in shape. 

1. In a shock absorbing load take-up apparatus for containers having a supporting frame and rotatable bolts disposed thereon and adapted to be inserted into corresponding fittings in the container, the improved rotatable bolt mounting comprising: a. an outer housing attached to said supporting frame, b. an inner housing attached to said rotatable bolt and coaxially mounted within said outer housing so as to slide relatively tHereto in a direction parallel to the longitudinal axis of said outer housing, c. resilient buffer means interposed between one end of said inner housing and one end of said outer housing, and d. means to prevent relative rotation between said inner and outer housings.
 2. A device as claimed in 1 wherein the inner housing supports all actuating and monitoring elements such as electric and hydraulic drives, switching apparatus and safety trip circuits.
 3. A device as claimed in claim 1 wherein a downwardly extending tracer pin, adjoined by a flexible conduit, is disposed in the inner housing.
 4. Apparatus as claimed in claim 1 wherein said resilient buffer means is under prestress.
 5. The improved load take-up device of claim 1 wherein said resilient buffer means comprises a cellular plastic material, such as polyurethane, having a high work absorption capacity.
 6. The improved load take-up device of claim 1 wherein said resilient buffer means comprises an hydraulic damper.
 7. The improved load take-up device of claim 1 wherein said means to prevent relative rotation comprises: a. an opening in said outer housing having a polygonal cross section, and b. a correspondingly polygonal extension attached to said inner housing and extending through said opening in said outer housing.
 8. The improved load take-up device of claim 7 wherein an actuating arm for causing rotary movement of said rotatable bolt is attached to said extension by means of a spherical bearing.
 9. The improved load take-up device of claim 1 wherein said bolt is rotatably attached to said inner housing.
 10. The improved load take-up device of claim 1 wherein an actuating arm for causing rotating movement of said rotatable bolt is attached to said bolt by means of a spherical bearing.
 11. The improved load take-up device of claim 1 wherein said inner and outer housings are generally cylindrical in shape. 